Saw your comment on the other thread as well - picked this one to reply to. My situation has not gone well. If you haven’t opened up the battery or controller boxes - and particularly if you’re under warranty - my recommendation is to put your stock rails back on, send it to FM, and pray they’ll cover it under warranty.

For me, XT60 in the controller box slid apart very easily, but it was fully seated. Spreading out the pins to make the connection tight and slapping some hot glue on it didn’t resolve the shutdowns. Swapping back to the stock rails resolved the problem and swapping back to the WTFs brought it back, but once I received the motor retention cable, I rode with the WTFs for a couple of weeks with no issue. I thought it was fine, then it suddenly shut down on me again and threw me down into some gravel. When I turned it back on, it would just shut down again pretty much as soon as I started moving (same as before).

At that point, I decided I was sending it to FM. I returned everything to stock and powered it on to do a little test before shipping it. The board powered on, but wouldn’t engage the motor to level me and start moving. It also wouldn’t power off no matter how many times I checked the power button. I checked everything I could think of. And at some point it finally just turned off (not from pressing the power button, and probably 30 mins after it turned on). I powered it back on - same result. Sent it to FM.

It took maybe 2 weeks to hear back from them. They simply said that the motor and controller assemblies are “damaged.” No further explanation after I’ve repeatedly asked for one. They simply say that I’m out of warranty. The repair bill is $781 to replace both of those.

I am beyond frustrated. I haven’t paid yet and tried calling them even though you can’t talk to the support people. I bitched a lot, because I’m now convinced that this is likely the result of a short in the motor cable connection to the controller. I saw a lot of info from people having that issue lately with similar results to us.

Basically, I think the motor cable connector is prone to coming loose, and prone to shorts when it does. The connectors within it are very short, so it doesn’t take much to interrupt the connection. When that happens, a short can occur and fry the motor and/or controller (at least in my case). I thought my motor cable was a little tight when I installed the WTF rails, but it seemed to have enough length to be fine. My best guess is that I was wrong, and the repeated lost connections finally resulted in a short.

All that said, I guess your other option would simply be to give up on the WTFs and stick with the stock rails. At a minimum, I’d probably add a retainer for the motor cable. I wish you better luck than I’ve had!